File Extensions

E2B looks at the file extension to decide how to boot to the payload file. To change the way a payload file will be executed by E2B, you can simply change its file extension, for example if you rename fred.iso to fred.isomem then E2B will load the file into memory before executing it. 

Note: If you want your ISOs and other files to work with agFM and Ventoy, I strongly suggest you use file extension override suffixes and keep the file extension unchanged – e.g. use WinPE_.isope01.iso instead of WinPE.isope01. The special filename ends in _.isope01 but the extension is still .iso.

A whole range of ‘Special’ (non-standard) E2B file extensions are recognised by the Easy2Boot menu system (see below).  If you are not sure what file extension will work best and it is an ISO file, use .isoask so that you can test all of them until you find one that works!

Note that the agFM menu system only supports a sub-set of E2B special file extensions, so some special file extensions may not work when using the agFM menu system.

File extensions are not case-sensitive. If you wish to see exactly what grub4dos code is run for each file extension – please look at the code in the file \_ISO\e2b\grub\QRUN.g4b. For example:  the lines under the label :.isoWIN in QRUN.g4b will contain the grub4dos commands that will be run for any xxxxx.isoWIN file.

When selected from the E2B menu and if the extension is recognised by QRUN.g4b, the file will be executed. The file extension determines how it is executed by E2B and grub4dos. 

Note: All files (except those files with file extensions of .bat, .xml, .cmd, .txt, .exe and a file with no dots anywhere in it’s name) are added as menu entries, but only files with the files extensions listed below will be recognised by E2B and QRUN.g4b. 

Tip: Always try a filename with no spaces or special characters first. If it works, then you can try renaming it – e.g. first try Windows_10_x64.iso – if it works then try ‘Windows 10 64-bit.iso’ so that the menu entry is more readable. Most (but not all) file types will work if they contain spaces and special characters (but avoid = and & in all file names).

File extension suffixes (not case-sensitive)

If you add pwd (e.g. fred.isopwd) to almost any file extension, E2B will prompt you for a password (which is defined by the variables ‘pwd’ or ‘menupwd‘ in your MyE2B.cfg file). The default password is easy2boot. See here for more details.

File extension suffixes work in all E2B menus except \_ISO\WINDOWS\xxxx sub-menus (you can only use file extension suffixes PWD, 32, 64, 4GB and 3GB in Windows Install Vista-SVR2009 menus, XP ISOs must use .iso – E2B v1.94+).

  • If you add AUTO to the end of a .imgPTN family file extension, the user will not be prompted before switching the image and loading the CSM menu (.imgPTNxxxx files only).
  • If you add 32      to the end of the file extension, the payload will only be listed in menus on 32-bit systems (v1.62+).
  • If you add 64      to the end of the file extension, the payload will only be listed in menus on 64-bit systems.
  • If you add pwd   to the end of the file extension, the user will be prompted for a password before it is run.
  • If you add 4GB   to the file extension, the payload will only be listed in the menu if the system contains more than 4GB RAM (v1.A4+).
  • If you add 3GB   to the file extension, the payload will only be listed in the menu if the system contains  less than 4GB RAM (v1.A4+).
  • If you add NCQ to the file extension (non-contiguous+quiet), the payload will not prompt the user with suggestions, redir will be set and will not try to make the file contiguous (v1.B0+).
  • If you add QUIETP to the file extension, redir and redirp will be set so that all messages will be reduced (v1.B0+).
  • If you add QUIET to the file extension, redir will be set so that messages will be reduced (v1.B0+).
  • If you add ORDER to .imgPTN file extension to re-order partitions – may prevent USB key from MBR booting but enable UEFI booting – see .imgPTN section below (v1.B0+).
  • If you add X4filename to the end of a .imgPTN extension, the partition image filename will be added as partion #4 – see .imgPTN section below – X4filename must be at the very end of the extension (v1.B0+).
  • ALBA23 – used after .imgPTN file extensions to make the new partition active, force the BIOS to use LBA addressing and keep existing partitions 2 and 3.

Do not use 32 and 64 added to the same file. Do not use 3GB and 4GB added to the same file. 


Ubuntu.iso64                      will only appear in the E2B menu if a 64-bit CPU is in the system. 
Windows10x64.isopwd64    user must enter password before ISO can be used (not listed in menu if 32-bit CPU)
Clonezilla.imgPTN32  will only appear in the menu if run on a 32-bit CPU.
Hirens_15.2.isowinvhpwd   will ask the user for a password (set by pwd or menupwd) before it will boot to the file.
Dium.imgPTNlbaa23auto   will not prompt user before switching the image.
Ubuntu_64-bit.iso4GB      will only appear in the menu if system has more than 4GB of system memory.
Ubuntu_32-bit.iso3GB         will only appear in the menu if system has less than 4GB of system memory.
Windows10x64.isoNCQ        will try to boot even if not contiguous
Windows 10 x64 1909.imgPTNpwd  will ask for password before switching in image file 

Extension suffixes can be combined – e.g. Ubuntu_64-bit.iso4GBpwd64ncqquietp 

Also, note that the E2B menu system arranges the menu entries alphanumerically, but E2B will not display the first four characters if the fourth character is an underscore. So a file named a23_Winpe_.isope01.iso will be listed in the E2B menu system as simply 'Winpe' (see Change menu order). Under agFM and Ventoy however, it will appear as the full file name: 'a23_Winpe_.isope01.iso'. By using a four-character prefix, e.g. nnn_ you can change the order of the files listed in the menu.

File extension override suffixes

You can force E2B to boot from a payload file as if it had a different file extension but still keep the original file extension (E2B v1.A9+).

Filename format:      anyfilename_.forceextension.ext         (the file extension .ext is preceded by _. and the extension that you want to force E2B to use) 

Note: agFM will also use the forceextension override (if valid for agFM) or you can also define a separate override just for agFM – see here for more details.

If you add the desired special E2B file extension after the file name and an underscore, then that file extension ‘forceextension‘ will be used by E2B instead of the actual file extension.

For example, if you have an ISO file but you want it to run as if it had a .isofira01 file extension, you can add _.isofira01 as a file override so  myxp.iso will run as if it had been named myxp.isofira01 if you give it the name myxp_.isofira01.iso. This means that the file will still keep the .ISO file extension which may be more convenient if you are using a Zalman\IODD device as your E2B drive or if you want to keep the file extension unchanged for other reasons. 

For files which must end in .iso such as WinBuilder ISOs or Windows ISOs, you can use an override of _.isodef.iso to suppress the E2B prompts – e.g. WinBuilderPEx86_.isodef.iso. 

VHD and WIM files, you could use BootPE_.wim64.wim or perhaps BootPE_.wimpwd.wim. 

Other examples are:  Medicat_.vhdhdd.vhd, Myxp_OS_.vhdboot.vhd or Ubuntu64_.isodef.iso.

Note: You can use a .mnu file instead to force any payload file to run as if it had a different file extension using, for example: 

title Run Ubuntu64\n
qrun.g4b  force.isodef  $HOME$/Ubuntu64.iso

The special override of xxxxxx_.WinNTSetup.iso will cause WinNTSetup.exe to automatically run if you have added WinNTSetup.exe to the E2B USB drive and the file is a Windows install ISO. 

The menu entries can also be suppressed (not listed in the menu) by including an override with extension suffixes such as  ’32’, ’64’, ‘3GB’ or ‘4GB’, etc. for instance:


will only be listed in the menu on systems with 64-bit CPUs and will prompt for a password when selected.

Windows8_.vhd4GB.vhd will only be listed on systems with 4GB or more of RAM.

Windows10PE_.wim64.wim – will only be listed on 64-bit systems. 

This is useful if the extension cannot be changed (e.g. file extension must be .vhd or .wim or .iso in versions of E2B before v1.B5). 

Note: File extension override suffixes are ignored by SWITCH_E2B.exe, image files must have an extension starting with .imgPTN. 

File name prefixes

E2B will order files in the menu alphanumerically.

E2B will not display the first characters in some case:

  1. Characters _*_ are ignored – e.g. _ABC_Ubuntu64.iso will be displayed in the E2B menu as Ubuntu64
  2. The first four characters are not displayed if the fourth character is an underscore – e.g. 300_Ubuntu64.iso is displayed as Ubuntu64.
This allows you to pre-determine the order of the .mnu and payload files, e.g.
100_Ubuntu x64_.isodef.iso
200_RedHat Server 9_.iso83.iso
300_Windows PE x64_.winiso.iso
330_DLC Boot 3.6_.isohw.iso
340_Gandalf WinPE R3_.isomap.iso
350_Gandalf WinPE R5_.iisodef.iso
370_Strelec 2020_.isowin.iso

I recommend using a letter followed by two numbers. This allows you to also use the first-letter jump feature in the agFM menu –

a10_Ubuntu x64_.isodef.iso
d20_RedHat Server 9_.iso83.iso

File name suffixes

The E2B menu system will recognise q and ncq at the end of a file name (not file extension) and treat the file in a different way: 

*Q.ISO – .ISO filenames ending in the letter Q.iso or q.iso (Q\q for ‘quiet’) and with a .ISO file extension (e.g. thisismyisoQ.iso) will suppress the ‘autosuggest‘ text usually displayed by E2B. Useful for WinBuilder-based WinPE ISOs which must use the file extension .ISO. Not case sensitive. You can also use myfilename_.isodef.iso instead.

*NCQ.* – No ‘not-contiguous’ warning messages are shown if the file is not contiguous (NCQ = not contiguous and quiet). Useful for WinBuilder-based WinPE  (use *NCQ.ISO) and other WinPE ISOs which are not contiguous but still boot OK (v1.98+). Not case sensitive.

  • WinBuilderPESE10q.iso
  • Windows7InstallNCQ.iso

Add a .txt file

*.TXT – If any payload file also has a matching .txt file of the same file name (e.g. Ubuntu.iso and Ubuntu.txt) this will also automatically suppress the ‘autosuggest‘ text usually displayed by E2B. The .txt file will contain the menu entry text which must contain a title or iftitle command line and up to four lines of help text which will appear under the menu when the menu entry is selected by the user.

If you use a matching .txt file for a payload file, then the menu will always be listed, unless the .txt file also tests for 32-bit or 64-bitness. e.g. If using files fred.iso64 and fred.txt, a menu entry will be displayed on both 64-bit and 32-bit systems, unless you add extra code to the .txt file to check which CPU is present – see here for details. If the payload is not listed as expected, check the .txt file for syntax errors.

List of file extensions recognised by the E2B Menu system

Recognised file extensions and their run actions are listed below…

You can use the special E2B extension with _. in front as a file name suffix – e.g. Ubuntu 13 x84_.isodef.iso – then the extension will remain as .iso and so can be booted using Ventoy.

Note that the agFM menu system may not recognise some of the non-standard extensions.

Also Ventoy only recognises standard file extensions, so keep the original extension and add in E2B and agFM suffixes to the filename to control how it is booted by E2B and agFM.

.iso – maps the ISO file (if contiguous) and also creates a new partition containing the ISO contents – use for linux and WinBuilder WinPE ISOs and others. If ISO file contains Windows install files WIMBOOT will be used to try to run the ISO as a Windows Installer + Setup.exe (v1.A8+). Depending on your configuration settings in MyE2B.cfg, a .iso extension will auto-suggest alternative extensions for a particular payload file and will delay for 6 seconds to allow you to choose (with a timeout).
Tip: Some payloads require a .iso extension (e.g. WinBuilder ISO files). For ‘quiet’ booting with no auto-suggest prompt, ensure the last letter of the filename ends in q or Q, e.g. WinPESE10_2016_x86q.iso. Create a matching .txt file if you want to change the menu entry text. You can instead use the file extension override feature (e.g. Ubuntu_.isodef.iso). .isodef, .isodefault – same as .iso but the QRUN auto-suggest feature is disabled so the user doesn’t get prompted with an alternative suggestion.
    Tip: use .isodef64 for 64-bit ISOs so that they are not listed in the E2B menu on 32-bit systems. Most WinBuilder ISOs must have a .ISO file extension.
Note: If PT grub4dos variable is set in your .mnu file to a partition type (e.g. set PT=0x83) then Partition 4 will be created with that partition type instead of the default Type 0x0 which is not detected by Windows. Note that on reboot, E2B will ask you to delete Partition 4.
.iso83 – sets Partition 4 as the ISO image and uses Type 0x83 for the partition type. Use if normal type 0 partition is not recognised by Linux ISOs. Note that on reboot, E2B will ask you to delete Partition 4. Useful to avoid registration with RHEL ISOs rhel-baseos-9.0-x86_64-dvd_.iso83.iso, etc. E2B v2.14e and later. ISO must be defragmented.
.isoask – asks the user each time which of the special options should be used – useful to determine which extension works best.
.isomem – loads the whole ISO file into memory and also creates a new partition containing the ISO contents (if contiguous) – use for non-contiguous linux ISOs and XP-based ISOs and Hirens ISOs (may not always work depending on payload type!).
.isowin – as .isomem but does not load ISO into memory unless it is non-contiguous, and then boots from setupldr.bin or \ntldr or \bootmgr if possible – use for WinPE ISOs – e.g. Symantec Recovery ISOs
.isolinux – tries to boot from ISO using isolinux.bin or \boot.isolinux.bin or \boot\syslinux.bin if possible
.isogrub – tries to boot from /menu.lst or grldr within the ISO
.isomemgrub – same as .isogrub but loads ISO into memory first (file does not need to be contiguous) (E2B v1.B7)
.isoforce – loads firadisk floppy disk image and forces grub4dos to boot from the ISO even if it doesn’t think it is bootable – use for CentOS ISOs
.isofira – maps the whole ISO file (if contiguous) or loads it into memory (if not contiguous) and also loads the firadisk floppy image as fd0 also if Windows ISO, will load ISO as virtual cd – use for BartPE\Strelec PE based ISOs
.isofira01 – maps the whole ISO file (if contiguous) or loads it into memory (if not contiguous) and also loads the firadisk floppy image as fd0, swaps hd0&1, also if Windows ISO, will load ISO as virtual cd  – use for BartPE\Strelec PE based ISOs
.isomap, .isoloop, .isoagfm – for compatibility with agFM – same as .isodef.
.isomap01, .isoloop01, .isoagfm01 – for compatibility with agFM – same as .iso01.
.isomemfira – loads the whole ISO file into memory and also loads the firadisk floppy image as fd0 – use for BartPE\Hirens XP PE based ISOs
.isomemF01 – loads the whole ISO file into memory and also loads the firadisk floppy image as fd0, swaps hd0&1 – use for ERD/MSDaRT 5 XP ISOs
.isowinvH– loads the ISO and also WinVBlock as a floppy image – does not swap hdo/hd1 – useful for booting Hirens CD and DLC multiboot ISOs
.isoHW – combines .isoPE with .isowinVH – use for Hirens\DLC ISOs which boot to WinXP and Win7/8/10. For correct Win7/8/10, a Removable E2B USB drive or Helper Flash drive is required – otherwise manually run \_ISO\e2b\firadisk\LOADISOPE.cmd after booting to Desktop. v1.78+.
.isomemwinv– loads the ISO into memory and also WinVBlock as a floppy image – useful for booting ERDCommander, BartPE and other XP PE based ISOs if they are not contiguous
.isogz – loads the ISO into memory – use for a gzip compressed ISO.
.isoBSD – loads a .imgptn partition image file as ptn 1 and the BSD ISO as ptn3 and then boots to BSD (E2B v1.A5+). Note: This swaps out the E2B partition with a small FAT partition but on the next MBR-boot, the E2B partition will be restored.
.isoboot – boot using ISOBOOT linux kernel parameters (for linux ISOs only), files can be non-contiguous (E2B v1.B0+).
.isoe0 – used to boot Windows PE ISOs which give a blank screen after booting on some systems that have a buggy BIOS. – e.g. some Dell PCs – see here for details.
.isomemE0– as .isoe0 but loads ISO into memory. – e.g. some Dell PCs – see here for details.
.isowinvE0 – as isowinv but with a special e820cyles=0 patch to boot WinPE-based ISOs that give a blank screen after loading – e.g. some Dell PCs – see here for details.
.isowinvHE0 – as isowinvH + e8020cycles=0 patch (see above)
.isoPE – use for WinPE v2/3/4 (Vista and later) WinPE ISOs. If the extension is .isoPE then when wpeinit is run by WinPE, it will mount the .isoPE file as a virtual CD/DVD drive letter. Note: This requires a USB Flash drive (or ‘Helper’ flash drive) – E2B v 1.07Beta and later versions only. The drive letter can be changed too. Boots to /bootmgr. Removable flash drive required. Swaps hd0-hd1.
.isoPE01 – as .isoPE but swaps hd0 and hd1 over so that the internal hard disk is hd0 – useful for diagnostic WinPE’s that expect to be booted from a CD and Vista/7/8 ERD/MSDart. Boots to /bootmgr. Removable flash drive required. Now same as .isoPE.
.isoPECD – as .isoPE, but boots from the ISO boot code instead of bootmgr – use for ‘compound’ ISOs which have their own boot menu and can boot to PE and other payloads. Removable flash drive required. E2B v1.81+
.isoPE01CD – as .isoPECD but swaps the USB drive with the first internal HDD – use if the ISO gets ‘confused’ by the USB drive being disk 0 during booting. Removable flash drive required. E2B v1.81+
.iso01 – same as .iso but swaps over hd0 and hd1 so hd0 will be the internal HDD. (v 1.11 and later)
.isoDOS – use for DOS-emulation bootable ISOs which normally load CD drivers to access the CD, all CD contents will be found on the B: FAT32 volume once booted to DOS. Note: DOS 6 cannot access the FAT32 B: volume – use DOS 7 or later.
.isoDOS01 – as .isoDOS but swaps over the USB boot drive with the internal hard disk so that the internal HDD is drive 0 – use for Win98 Install ISOs, etc. – see also .imgfdhd01.
.isoPUP – use for Puppy linux and other similar linux ISOs
.isomacpup – use for Macpup ISOs (modifies the ISO to remove (cd) in menu.lst)
.isopersist – use for ubuntu (casper) isos + persistence files (v1.98+).
.isopersistdebian – use for Kali\Debian-based ISOs which use a volume named ‘persistence’ and a persistence.conf file for persistence (v1.B4+) – see here for details.
.isoWB – use for WinBuilder PE ISOs based on Vista or later versions of Windows (deprecated – use .iso now) – see here for details..
isonousb – loads ISO as CD (0xff), maps USB drive as fd0, removes USB drive from BIOS hard disk list.  Useful for DOS if you don’t want your USB drive to appear as a hard disk. v1.61+ more details here
.isoBF – permanently patches the ISO file to remove bootfix.bin. This patches the ISO file so that it will not ask the user ‘Press any key to boot from CD/DVD…’ on booting. Once patched, you can rename the file to a different extension if you wish (v1.76+).
.isoDPMS – loads XP 32-bit SATA\SCSI\RAID driver – used for DaRT5\ERD5 XP 32-bit based ISOs (only works with DPMS version of E2B). E2B v1.A7+).
.isoPELD – boots to \sources\boot.wim file and loads ISO as drive Y:. If Setup.exe or RecEnv.exe is present, offers option to run them, else goes to command prompt. WIM image must contain \Windows\Boot\PXE\bootmgr.exe. If WIMNO variable is set to a number (e.g. set WIMNO=3) then that image inside the boot.wim will be used (E2B v1.A8+). If a .cmd file exists in the same folder and with the same name as the ISO, it is called. The .cmd file can contain a line such as ‘set ISOLETTER=K:’ so that the ISO is mounted to K: instead of Y:. You can also add code into the .cmd file (e.g. to copy files into X:).
.isoPELD1 – same as .isoPELD but forces bootmgr to load index #1 image (E2B v1.A8+). 

.gzmd – for compressed .gz format file, loads memdisk and then the .gzmd file using initrd
.krn, .lkrn – kernel files (such as used by iPXE and (v1.78+). Note: Use E2B v1.B5 or later if you have spaces in filenames for .wim and .VHD files (or else you will get Error 0xc000000f).

.vhdboot – a bootable .VHD virtual hard disk image (must not be a dynamic vhd) – boots vhd as hd0. All boot files must be inside the VHD file. Typically used for XP VHDs. (Note: equivalent to .vhd in earlier E2B versions – now changed to .vhdboot in E2B v1.69+). v1.74+ also adds in a firadisk ‘load vhd’ command for vhd’s that contain the firadisk driver.
.vhdmem – same as .vhdboot but the whole vhd file is loaded into memory (use if .vhd crashes and for faster operation once booted – obviously needs loads of memory!). The VHD must contain all boot files and be if the ‘fixed/static’ type (not dynamic).
.vhd,.vhdx – NT6-based (bootmgr) VHD and VHDX file for directly booting Windows 7/8/10 .VHD virtual hard disk files. e.g. a 25GB WindowsToGo VHD can be directly booted to. Note that you may need to add a copy of bootmgr to the \_ISO\e2b\grub\DPMS\NTBOOT.MOD folder as bootmgr is not included in the E2B download for copyright reasons. The vhd file does not need to contain bootmgr or a valid BCD. The vhd file does not need to be contiguous. v1.69+. Note: suffixes 64 and 32 (e.g. .vhd64) are not supported. Dynamic VHD\VHDX files may work if there is enough free space on the USB drive to expand.
.vhdhdd – for bootable fixed VHD HDD images which have boot code in MBR. VHD mapped as last disk. (E2B v2.14h+)
.firavhd, .vhdfira – loads a .img image file as a hard disk image (hd0) and adds a firadisk virtual floppy to force the firadisk driver to load the image on boot (v1.74+).
.vhdgrldr – Load a vhd as hd0 and boot to (hd0,0)\grldr (grub4dos inside the VHD) or if not exist (hd0,0) PBR or if not exist (hd0) MBR (v1.75+). Try it for non-Windows VHD files. 
.vtoy – Ventoy raw image, fixed .vhd and fixed .vdi Linux OS’s can be booted. The Linux must have the applied. See here. Supported by E2B, agFM, Ventoy and ‘Ventoy for Easy2Boot’ (E2B v2.16+).
.wim – NT6-based (bootmgr) .WIM file for directly booting Windows 7/8/10 .wim files containing a RAMDisk PE3 image. Only WIM files containing a single image are supported (first image is booted). Note that you may need to add a copy of bootmgr to the \_ISO\e2b\grub\DPMS\NTBOOT.MOD folder as bootmgr is not included in the E2B download for copyright reasons. The wim file does not need to contain bootmgr or a valid BCD. The wim file does not need to be contiguous. v1.69+. Note: suffixes (e.g. .vhd64) are not supported. .zip – uses memdisk to load a zip file into memory as a floppy disk (e.g. use for which contains dos622.ima).bin – use for binary executables such as memtest86.bin.
.wimboot – uses wimboot (from the iPXE project) instead of NTBOOT to boot a .wim file. Use a file extension of _.wimboot.wim if the wim file fails to boot using .wim. You can make all .wim files boot using wimboot by adding ‘set WIMBOOT=1‘ to the \_ISO\MyE2B,cfg file. (E2B v2.16+).

.img – will use .imghd unless the size of the image file is the same size as a floppy drive image (e.g. 720k, 1.44M, 2.88M), in which case it will use .imgfd. Use .imgfd or .imghd extension to force E2B to use the correct type if .img does not work. Swaps USB with first hdd and maps image as hdd0 (hdd1 will be USB, first internal will be hidden).
.imghdd – as above but just maps image as a new (last) hdd number, so USB is still hd0 and first internal=hd1, etc.
.imghd– Swaps over hd0 (USB) with hd1 (first internal hdd), the image is directly mapped if contiguous or loaded into memory if not – image is mapped as hd0
.imgmemhd, .imgmem – Swaps over hd0 with hd1 and maps the file as hd0 in memory using –mem
.imgfd, .ima, .imafd, .imgmem, .img.gz, .ima.gz, .imagzmem, .gzfd, .imamem, .imgmemfd, .imgfd – These will all cause the file to be loaded into memory and to be mapped as a floppy disk image.
.imarw – loads file as fd0 but not into memory – this means you can change the contents of the ‘floppy’ when you boot to it and the changes will be persistent (v1.54+) – i.e. the file contents may be changed the next time you boot from it! You can thus add or delete files once you have booted from the image. Must be contiguous.
.imgfdhd01 – loads floppy disk img file as fd0 into memory and swaps hd0 with hd1 – use for KonBoot fdd image where hd0 needs to be the internal hard disk and not the USB boot drive (E2B v1.08 and later).
.imgnousb, .imanousb – loads a floppy image into memory as fd0, maps USB drive as fd1, removes USB drive from BIOS hard disk list. Useful for DOS if you don’t want your USB drive to appear as a hard disk. Note: DOS may not be able to fully access a large FAT32 floppy drive B; as fd1. v1.61+  more details here

.imafdhdd0 – loads file as a large floppy (not loaded into memory if contiguous) as fd0, maps internal HDD as hd0, no other drives visible, then boots to IO.SYS (DOS) or KERNEL.SYS (FreeDOS) or boot sector. For instance, convert DOS-based ISO to .imgPTN file, add DOS boot files and rename to .imafdhdd0 (E2B v1.77+). See Win98 blog here.
.imghdlinux – finds a type 0x83 partition in the disk image file and attempts to boot from it. Must be contiguous. (v1.76+)
.imghdPT – as .imghdlinux, but the partition type should be set first using ‘set PT=0xhh’ where hh is the hex partition type – e.g. 0x83 or 0xAF. You can use this in a .mnu file by setting PT (e.g. set PT=0x83) and then calling /_ISO/e2b/grub/qrun.g4b force.imghdPT $HOME$/xxx.img. (v1.76+)
.imgPTNREP3 (agFM v1.51+ only – not E2B) – replaces partition 3 with the contents of the file. Can be used for Mac OS X
.dmg and .dmgHFS – Single-partition HFS+ bootable partition type AF .dmg files (usually Hackintosh Installer files) – e.g. Yosemite-Zone.dmg. see here.
.HFSptn, .HFS – for bootable partition images of an HFS+ (partition type AF) – e.g. as made by UniBeast. see here.
.haiku, .imgBeOS – for Haiku ‘anyboot’ images – makes a permanent ptn #4 entry for type EB on the USB drive which needs to be removed on reboot. see blog here

.cfg – These files are E2B configuration ‘theme’ files and should contain the contents of a valid MyE2B.cfg file beginning with !BAT. When selected it will overwrite a dummy \_ISO\MyE2B.cfg file (which should be blank and at least as big as the .cfg file selected) and relaunch E2B so that the new Menu settings in the \_ISO\MyE2B.cfg file take effect. (v1.55+). The \_ISO\MyE2B.cfg file must be at least as big as the selected .cfg file. The \_ISO\MyE2B.cfg file should be contiguous. A large blank file, suitable for use as the \_ISO\MyE2B.cfg file can be found at \_ISO\docs\mythemes\$Default E2B Menu.cfg. See the ReadMe.txt file for more details. Useful for switching to different ‘skins’. 

.txt – used for ‘title’ or ‘iftitle’ menu entries. .txt files are ignored unless there is a payload file of the same name in the same folder – see here

.bmp, .jpg – load file as background wallpaper (E2B v1.A1+). Any animation should be stopped first using F2, if wallpaper will not change. 

.uni.gz, .f24 – load font file (.uni.gz is assumed to be 16 pixel high font, .f24 is assumed to be 24 pixel high font) (E2B v1.A1+). 

.help – a plain ASCII or UTF-8 text file which is displayed to the user – see here (E2B v1.A6+). 

_.WinNTSetup.iso – (e.g. Win10x64_.WinNTSetup.iso) causes the ISO to boot to WinPE, load WinNTSetup.exe and load the ISO as the source file into the WinNTSetup form. If you place the file in a \_ISO\WINDOWS\WINxx folder, then the ‘Repair’ option will instead run WinNTSetup. The WinNTSetup executables must first be added to your E2B USB drive.

.zip – use only for compressed floppy disk images. The disk image will be decompressed and run from memory. Same as .gzmd.

.imgPTN Partition image file extensions (v1.51+)

All .imgPTNxxx files MUST be contiguous. Not all combinations are recognised by agFM.

Suffixes that can be added for .imgPTN files (not case sensitive):

  • 23=Partition entries 2 and 3 will be kept so they are accessible in CSM mode (add ’23’ to the end of a valid .imgPTN file extension)
  • REP3 – The image file will replace only partition 3. The .imgPTNREP3 file must be on the 3rd partition (not partition 1 or 2).
  • X4ffff – where ffff specifies the name of a partition image file which will be loaded as partition #4, the search order is: ((current folder)\ffff and then \_ISO\ffff – e.g. \_ISO\LINUX\UBUNTU64.imgptnX4winpe would load that file and also load the file \_ISO\LINUX\winpe  or \_ISO\winpe as the 4th primary partition (E2B v1.B0+).
  • a=active – marks the first partition as active (bootable). An active partition may be required for some WindowsToGo first boot-time images to avoid a ‘Windows could not complete’ error on first boot.
  • LBA=forces BIOS to use LBA addresses
  • na=not active – does not mark any partition as Active (bootable)
  • ORDER – some UEFI BIOSes will refuse to UEFI-boot if the start of each Primary partition is not in ascending order. Use this if more than one partition contains an image and you want to UEFI-boot. Note that this will usually break MBR-booting from the E2B menu however unless you modify the non-E2B images. Not recommended!

Note: The partition image extensions .imgPTN, .imgPTN23 or . (no file extension) are the most often used.

.imgPTN, .imgPTNLBAa, .imgPTNaLBA – (a=active) Makes the first partition Active. removes all E2B drive partitions and replaces them with one partition pointing to this partition image. The E2B files must be installed on the first partition and grub4dos must be installed to the MBR. The .imgPTN file must contain grldr and a special version of menu.lst. Usually, an .imgPTN file is made using MakePartImage.cmd.
Note: if the file extension is just “.imgPTN” and there is a hidden Type 21 partition present (as created by RMPrepUSB or the MAKE_E2B_USB_DRIVE.cmd batch file by default) then the hidden partition will not be removed when you switch partitions. If you think this may be preventing the firmware from ‘seeing’ the UEFI boot file, try a file extension of .imgPTNLBAa instead.

.imgPTNLBA – Modifies the partition table to force the BIOS to use LBA addressing but does not make the first partition Active. 

.imgPTNAUTO – same as .imgPTN but no user prompt to switch partitions – the CSM menu is immediately displayed with no user warning messages. See Sample_MyE2B.cfg file for a setting that will auto-run all .imgPTN files.

.imgPTNna, .imgEFIna – (na=not active) – same as .imgPTN but the partition is not marked as active.

.imgPTNa – same as .imgPTN but the partition entry uses CHS not LBA.

.imgPTN23 – same as .imgPTNLBAa23, partition entries 2 and 3 are not removed (E2B v1.99+)

.imgPTNLBA23 – same as .imgPTNLBA but partition entries 2 and 3 are not removed.

.imgPTNaLBA23, .imgPTNLBAa23 – same as .imgPTNlba but partition entries 2 and 3 are not removed and partition 1 is made Active. This allows you to boot from a Windows image file but still be able to access the 2nd and 3rd partition on the E2B USB Hard disk. v1.37+

.imgPTNa23, .imgPTN23a – same as .imgPTNa but does leaves partition entries 2 and 3 in the partition table – use for WinPE/WinToGo images on E2B USB hard disks where you want access to the 2nd and 3rd partitions when you boot from the image.  v1.37+

.imgPTNA5 – For use with a 2nd FreeBSD image file. Usually the .imgPTNA5 file is made from an empty folder and so just contains the CSM menu files. It is used in conjunction with a larger disk-image file of the same name but with no extension. This 2nd file is a FreeBSD ‘memstick’ image file which is a disk image containing a bootable FreeBSD A5 partition. An extension of .imgPTN can also be used with the same behaviour.

(no file extension) – If a *.imgPTN* file of the same name also exists (e.g. fred.imgPTNLBAa + fred), then when switching to fred.imgPTNLBAa, the file fred will be used as partition #3. The file must be contiguous. 

Using File Extensions with E2B

For instance, if you have fred.iso and it is a BartPE XP ISO, rename the extension to fred.isomemfira and it will be loaded into memory and a firadisk floppy image will also be loaded. If you just leave it as .iso, and it is contiguous, it will be directly mapped and no firadisk floppy image will be loaded and it may BSOD! .xxxxxxpwd – add pwd to the end of any file extension in a normal Menu Folder and E2B will prompt for a password before booting from it. If you want a different menu title to be used (rather than just the name of the file used in the menu), then make a new .txt file using Notepad. For example, if you have DOS622.imagzmem and you want a different title, add a new file called DOS622.txt to the same folder and add your replacement title line in the file (must start with the lower-case word ‘title‘) – e.g. title MS-DOS 6.22 Floppy Disk\n This boots the file DOS622.imagzmem 

More extensions can be supported by editing the \_ISO\E2B\grub\QRUN.g4b grub4dos batch file and adding a new extension section of code to the batch file. Let me know if you want me to support a new extension in the QRUN.g4b file for the next version. 

Tip: If you have an ISO file which does not boot correctly, rename it to .isoask – then you can try all of these options to see if any of them will work correctly. 

Note: The files can be listed in the menu with or without their file extensions (set by the EXTOFF variable in \_ISO\MyE2B.cfg). 

Suggested file extensions to use for different ISOs/payloads

  • Linux ISOs – just keep as .iso or use .isodef and ensure it is contiguous (see here if any problems)
  • Puppy Linux – try .isopup
  • BartPE/XP/XP Rescue ISOs – rename to .isowinv or .isomemwinv (if blank screen after boot, try .isowinve0 or .isowinvHe0)
  • Hirens ISOs – rename to .isowinvH or .isoHW (or .isomem for slow loading but faster operation) – or else try extracting the \HBCD or \DLC or \DLC1 folder to the root of the Easy2Boot USB boot drive. See here for more details. For multiple Hirens with full functionality, make a .imgPTN file from each one using MakePartImage.
  • Windows Install ISOs – these work best if placed in the correct \_ISO\Windows\xxxx folder (can also convert to .imgPTN for UEFI-booting)
  • HDDR2011 ISO – compress it to .gz file and use .isogz
  • Windows based ISOs that give a blank screen when Windows loads – use .isoe0,.isowinve0 or .isowinvHe0 – problem is due to buggy BIOS!
  • WinBuilder WinPE (v2/3/4) ISO files – use .ISO for WinBuilder ISOs – do NOT change extension and no spaces in filename – you can use an extension override – e.g. Win10PESE_x64_.isoNCQ64.iso.
  • Medicat, Bob Omb’s WinPE, etc. – convert to FAT32 .imgPTN file or try xxxxxx_.isomap64.iso
  • UEFI ISOs or MSDaRT ISOs – Create a FAT32 .imgPTN file using MakePartImage.cmd or use agFM menu system.
  • Windows To Go – create an NTFS .imgPTN file using MakePartImage – see blog or create a VHD and copy to a E2B menu folder.

If you are still having problems, check the \_ISO\docs\Sample mnu files folder to see if there is a .mnu file you can use (or modify slightly). You can also ask for help on the forum.There are also useful blog posts about E2B payloads listed here.

Finally, if all else fails, contact me and I will try to help. 

Compressed payload files

You can compress some types payload files (e.g. .ima) to a gzip format (e.g. using 7Zip) or for better compression, use a special LZMA format (using the LZMA tool in the \_ISO\docs\E2B Utilities folder).  

In general however, I suggest you do not compress your payload files, perhaps except for some DOS-based images. 

Compressed files must be decompressed and the entire file loaded into memory first before they are booted to. E2B\grub4dos automatically detects if a file has been compressed to gzip or LZMA format.

The file extension is not used by E2B to determine if a file is compressed or not. For instance, a LZMA-compressed DOS floppy image can be named .ima or .imagz. However, we need to ensure the E2B loads the whole payload file into memory and does not attempt to boot directly from the compressed payload file.

E2B can recognise a variety of file extensions that contain the characters ‘mem’ (e.g. .isomem, .vhdmem) and these file extensions can be tried if you want to try booting from a compressed file, because it will force the source file to be loaded into memory and decompressed before booting from it. 

Some payload files will boot successfully when compressed to gzip or lzma format using 7Zip (.gz) or LZMA (see \_ISO\docs\E2B Utilities\LZMA folder). For instance DOS floppy disk images will still work if compressed. E2B\grub4dos must decompress these files by loading them into memory first, this may take a while for large files. Also, any boot code which is loaded from the compressed file will not be able to access the compressed source file (e.g. ISO file) once it starts to boot, because the source file is in a compressed state which will not be understood by the boot code.

Further, E2B\grub4dos cannot use the partnew command to map an ISO or .imgPTN file to a partition table if the file is compressed, and so many payloads will be unable to fully boot if they are in a compressed format.

For these reasons, only payload files that can be loaded and executed from memory, such as DOS floppy images and simple, single-stage linux ISOs (.isomem), should be compressed. The file extension .zip can be used to boot from DOS floppy images that have been compressed using the ZIP format because E2B will use the memdisk utility to decompress the zip file and map it as a floppy image.

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